巻号一覧
5 巻 (1980)
- 4 号 p. 285-
- 3 号 p. 199-
- 2 号 p. 109-
- 1 号 p. 1-
5 巻, 4 号
選択された号の論文の9件中1～9を表示しています
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Yasusada Miura1980 年 5 巻 4 号 p. 285-304
発行日: 1980年
公開日: 2008/04/18
ジャーナル フリーRegulatory mechanisms of primitive erythroid cell differenti-ation are discussed. Chick or quail yolk sac cells at the definitive primitive streak stage were the main experimental materials. An intact endodermal layer was required for formation of well developed blood islands. Yolk sac cells were dissociated into single cells then reaggregated by centrifugation or on a gyratory shaker. Vigorous blood island formation was observed in the "reconstructed" yolk sac tissue. In this system, erythroid precursors have been proved to be sorted out first and then to differentiate into blood islands. Dissociation of embryos before formation of the primitive streak interfered with the formation of blood islands. Yolk sac erythropoietic presursor cells are much more radioresistant than are adult hemopoietic cells. Formation of erythroblasts and hemoglobin synthesis were much enhanced after treatment with dimethylsulfoxide and other murine leukemia cell inducers. These experi-mental results are compared with results of recent studies from other labora-tories on erythroid colony formation and on the induction of definitive erythro-cytes in yolk sac cells in organ culture.抄録全体を表示PDF形式でダウンロード (3531K) -
Takahiko Miyazawa, Chikako Sato, Hiroshi Hiai, Yoshimi Nishi, Mutsushi ...1980 年 5 巻 4 号 p. 305-314
発行日: 1980年
公開日: 2008/04/18
ジャーナル フリーA reticuloepithelial-like cell line (B6TE) was established from normal thymuses of 4 week-old C57BL/6J mice. The cells were polygonal and had a pavement-like arrangement in the confluent state. Desmosome-like structures and tight junctions were seen at the adjacent cellular mem-branes on electron microscopic observation. The doubling time was 24 h and the saturation density was 1 × 105 cells/cm2. The cell line had the ability to proliferate and differentiate bone marrow cells exceedingly well. When 1 × 105 cells/ml of nucleated bone marrow cells were cultured on an irradiated mono-layer of B6TE cells, the bone marrow cells multiplied greatly and reached 1.6 × 105 cells/ml after 7 days. Most of the proliferated bone marrow cells belonged to the myelocytic lineage. Mitotic and blast cells adhered to B6TE feeder cells forming a cluster in their early culture days. The feeder activity of B6TE cells was 5 times more potent than that of L cells and of mouse embryo fibroblasts. The interaction between the cell line and undifferentiated bone marrow cells should provide a useful model for the investigation of hematopoietic inductive microenvironme nts.抄録全体を表示PDF形式でダウンロード (4657K) -
Kazuko Tsuneoka, Mikio Shikita1980 年 5 巻 4 号 p. 315-321
発行日: 1980年
公開日: 2008/04/18
ジャーナル フリーThirteen cell lines, all of which had been adapted to grow in a chemically defined medium, produced colony-stimulating factor (CSF), but the production rates of the factor varied considerably among the cell lines. Rat liver parenchymal, monkey kidney, and rat spleen plasma cell lines were comparable to L-P3 cells in their CSF-producing activity. Isoelectrofocusing and gel-filtration chromatography in the presence of 6 M guanidine HC1 showed that the CSFs of the liver and kidney cell lines resembled L-P3 CSF, whereas the CSF of spleen cells differed from the other CSFs in its molecular properties. In addition, the CSF of the spleen cell line predominantly stimu-lated the formation of granulocytic colonies, but the L-P3 CSF and other CSFs mainly enhanced monocytic colony formation.抄録全体を表示PDF形式でダウンロード (707K) -
Kengo Sakaguchi, Yasuo Hotta, Herbert Stern1980 年 5 巻 4 号 p. 323-334
発行日: 1980年
公開日: 2008/04/18
ジャーナル フリーMeiotic cells of male mice (spermatocytes) have a very high DNA polymerase-β relative to polymerase-a activity. Similarly, the male meiotic cells of lily have a high ratio of the corresponding DNA polymerases, tentatively designated as B and A. In mice, the ratio is of the order of 50, and in lilies it is about 6. The helix-destabilizing protein of meiotic cells, the "R-protein", specifically stimulates polymerase-β (B) but has no effect on poly-merase-a (A) activity. Mouse R-protein has no effect on lily polymerase-B nor has the lily protein any effect on mouse polymerase-β. Stimulation occurs both in extracts and in isolated nuclei. Dephosphorylated or over-phos-phorylated R-proteins have no stimulatory effect on polymerase activity either in extracts or in isolated nuclei. The high polymerase-β (B) activity in meiotic cells correlates with the endogenously stimulated repair synthesis during meiosis. The interaction between polymerase-β (B) and R-protein may relate to their combined role in meiotic recombination.抄録全体を表示PDF形式でダウンロード (1311K) -
Fumiaki Nishiyama, Hiroshi Hirano1980 年 5 巻 4 号 p. 335-346
発行日: 1980年
公開日: 2008/04/18
ジャーナル フリーLectin-binding sites on the porcine thyroid follicle cell surface wereexamined using ferritin conjugated Ricinus communis agglutinin (Fer-RCA) as a cytochemical stain for sugar residues on the plasma membranes. The porcine thyroid gland was dissociated in an enzyme solution containing collagenase and trypsin. The dissociated non-cultured cells and the disso-ciated then cultured cells, either unfixed or aldehyde-fixed, were labeled with Fer-RCA and processed for transmission electron microscopy. On aldehyde-fixed cells, the tagged ferritin particles representing RCA-binding sites were more abundant at the apical surface than at the baso-lateral surface. On unfixed cells, patchy and sparse redistribution of the Fer-RCA binding sites was seen on the baso-lateral surfaces, whereas on the apical surfaces it was not clear. Recovery of the binding capacity for Fer-RCA at the baso-lateral cell surfaces took place within 1 h, when Fer-RCA-labeled, unfixed, disso-ciated cells were incubated in the culture medium without Fer-RCA. The en-zymatic dissociation procedure did not seem to change the RCA-binding sites in terms of number and the distribution pattern over all the cellsurfaces, but to some degree it caused higher mobility and easier detachment of RCA-binding sites on the unfixed baso-lateral cell surfaces. We concluded that thyroid follicle cells have regional differences for their RCA-binding sites in the distribution and redistribution patterns between the apical and the baso-lateral cell surfaces. These regional differences in the RCA-binding sites may represent plasma membrane polarity, morphologically and functionally, in these highlyorganized tissue cells.抄録全体を表示PDF形式でダウンロード (1758K) -
Terukatsu Sasaki, Toshio Sakagami1980 年 5 巻 4 号 p. 347-358
発行日: 1980年
公開日: 2008/04/18
ジャーナル フリーPlasma membrane glycoproteins of rat hepatocytes that had been exposed to subendothelial spaces of Disse were selectively radiolabeled by reduction with tritiated sodium borohydride after oxidation with neuraminidase plus galactose oxidase. The labeled glycoproteins were separated by polyacrylamide gel electrophoresis and located by fluorography.
Selective treatment with galactose oxidase and neuraminidase of glycoproteins and glycolipids exposed to spaces of Disse was made possible by perfusion of rat liver with an oxygenated phosphate-buffered saline containing the enzymes. After the perfusion, the blood-sinusoidal plasma membrane of hepatocytes was isolated from both the microsomal and nuclear pellets by the method of Touster et al. (J. Cell Biol. (1970) 47, 604-618). The carbon-6 aldehydes present in the plasma membrane subfraction were reduced back to galactose and N-acetylgalactosamine with tritiated borohydride.
One-dimensional polyacrylamide gel electrophoresis in sodium dodecyl sulfate resolved many 3H-labeled components ; none of these components was labeled to a significant degree when galactose oxidase was not added to the perfusion medium. About forty [3H]glycoproteins were resolved by twodimensional polyacrylamide gel electrophoresis according to the method of Imada et al. (Biochim. Biophys. Acta (1978) 507, 459-469). These [3H]glycoproteins were fractionated by a modification of O'Farrell's method.抄録全体を表示PDF形式でダウンロード (6231K) -
Kyoji Yamada, Michio Ito1980 年 5 巻 4 号 p. 359-366
発行日: 1980年
公開日: 2008/04/18
ジャーナル フリーAn efficient method has been developed for the synchronous and high frequent induction of meiosis in Saccharomyces cerevisiae. An exponential-phase cell population was treated with 0.1 M hydroxyurea (HU) for various periods, then it was transferred to a sporulation medium. The 5-h treatment with HU caused the accumulation of oversized pairs containing a parent cell and bud with a dividing nucleus. After transfer to the sporulation medium, all the buds developed into daughter cells in the first few hours, then both parent and daughter cells synchronously underwent meiotic division. In this synchronous system, meiosis occurred in more than 95 % of the cells, but the frequency of ascus formation and the spore number per ascus were not improved in comparison with the control cultures. Our results indicate that the ability of cells to undergo meiosis depends primarily on the size attained prior to sporulation induction.抄録全体を表示PDF形式でダウンロード (742K) -
Kengo Sakaguchi, Nori Kurata, Miyako H. Takegami, Michio Ito1980 年 5 巻 4 号 p. 367-377
発行日: 1980年
公開日: 2008/04/18
ジャーナル フリーThe role which DNA and RNA syntheses play in meiotic de-velopment was analyzed by the cytological effects of various inhibitors of nucleic acid synthesis in lily microsporocytes. Microsporocytes in meiotic prophase were cultured in vitro for discrete periods in the presence of inhibitors at various concentrations. Of the tested inhibitors eleven were effective. Many different cytological abnormalities were produced by these agents. The ab-normalities could be divided into two groups; the suppression of meiotic development and the induction of various types of chromosome aberrations. The effects of inhibitors that leads to developmental suppression in prophase cells was examined in detail. Significances of DNA and RNA syntheses in meiotic development are discussed.抄録全体を表示PDF形式でダウンロード (3094K) -
Machiko Taniguchi, Keiko Kobayashi, Jiro Ohta1980 年 5 巻 4 号 p. 379-382
発行日: 1980年
公開日: 2008/04/18
ジャーナル フリーMyosin was separated from Physarum myxoamoeba myosin B by ultracentrifugation, then purified by potassium iodide treatment followed by gel filtration.
The purified myxoamoeba myosin was similar to the myosin isolated from Physarum plasmodium. Myxoamoeba myosin was soluble at low ionic strength, but it formed bipolar filaments on the addition of 10 mM MgCl2. ATPase activity was activated by Ca++, but was inhibited by Mg++ and EDTA.抄録全体を表示PDF形式でダウンロード (387K)
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